Advanced Cu barrier/seed development for 65nm technology and beyond

A novel PVD sputtering source has been developed based on a high power-density concept. The new sputtering source dramatically increases the metal ion traction which improves TaN/Ta barrier and Cu seed step coverage and gap fill capability in Cu metallization. Successful ECP gap fill has been achieved on the most aggressive features currently available - 0.08μm 6:1 aspect ratio vias - when a 300Å Cu seed layer is deposited with this new source. Electrical test results based on the testing structure of 90nm technology node including parametric and stress migration, are equivalent or better than current processes. The new source will further extend the lifetime of PVD in the IC industry.